I had an 2007 4 cyl. (A company truck) that I put over 500K on it. You own a bullet proof vehicle that if u show some patience, it can be fixed. Don't try and save money by going to a cheap shop. It just isn't worth it, as you can see. The a/c repair should not have anything to do with it. If the shop disconnected the battery for any length of time, the truck could lose it ECM memory and will tend to die. It will re-learn itself after driving approx. 60 miles or so. A vacum hose(s) could be loose also or, a gummed up fuel pressure regulator.